This lovely vintage piece of Royal Copenhagen is from the Art pottery range or Aluminia Faience.
The bottle has a design in blue and purple and was designed by Inge Lise Koefoed as part of the Tenera range of pottery. Her mark can be seen to the back.
The bottle has a cork stopper complete with ceramic top. The cork has some little pieces that have come away from the base. It fits the neck but does not fit tightly.
The colours are strong and there is no damage to the piece. The piece is marked with a faint scratch to the backstamp to the underside indicating it is a seconds.
We think the reason for this is the little inclusion in the glaze to the neck shown in the last photo.
The vinegar bottle is 130mm tall.